import static org.codelibs.core.misc.AssertionUtil.assertArgumentNotNull;

import java.util.Iterator;
import java.util.NoSuchElementException;

import org.codelibs.core.exception.ClUnsupportedOperationException;
import org.codelibs.core.message.MessageFormatter;

/**
 * An {@link Iterator} that iterates through the inheritance hierarchy of a class towards its superclasses.
 * <p>
 * Usage example:
 * </p>

    public String toString() {
        StringBuilder ret = new StringBuilder().append(proto).append(":").append(server).append("[").append(endpoint);
        if (options != null) {
            final Iterator iter = options.keySet().iterator();
            while (iter.hasNext()) {
                final Object key = iter.next();
                final Object val = options.get(key);

  }

  @CollectionSize.Require(ONE)
  @CollectionFeature.Require(SUPPORTS_ITERATOR_REMOVE)
  public void testKeysEntrySetIteratorRemove() {
    Multiset<K> keys = multimap().keys();
    Iterator<Multiset.Entry<K>> itr = keys.entrySet().iterator();
    assertEquals(Multisets.immutableEntry(k0(), 1), itr.next());
    itr.remove();
    assertTrue(multimap().isEmpty());
  }

  @CollectionSize.Require(SEVERAL)

        }
    }

    /**
     * {@inheritDoc}
     *
     * @see java.util.Iterator#hasNext()
     */
    @Override
    public boolean hasNext() {
        return this.next != null;
    }

    /**
     * {@inheritDoc}
     *
     * @see java.util.Iterator#next()
     */
    @Override
    public FileEntry next() {
        final FileEntry n = this.next;

    assertThrows(NoSuchElementException.class, () -> iterator.next());
    assertThrows(IllegalStateException.class, () -> iterable.iterator());
  }

  public void testOf_one() {
    Iterable<String> iterable = MinimalIterable.of("a");
    Iterator<String> iterator = iterable.iterator();
    assertTrue(iterator.hasNext());
    assertEquals("a", iterator.next());
    assertFalse(iterator.hasNext());

        TestIterator iterator = new TestIterator(null);

        // Verify iteration
        assertTrue(iterator.hasNext());
        assertSame(resource, iterator.next());

        assertTrue(iterator.hasNext());
        assertSame(resource, iterator.next());

        assertTrue(iterator.hasNext());
        assertSame(resource, iterator.next());

        assertFalse(iterator.hasNext());

   */
  static class IteratorWithJdkBug6529795<T> implements Iterator<T> {
    Iterator<T> iterator;
    boolean nextThrewException;

    IteratorWithJdkBug6529795(Iterator<T> iterator) {
      this.iterator = iterator;
    }

    @Override
    public boolean hasNext() {
      return iterator.hasNext();
    }

    @Override
    public T next() {
      try {

        assertArgumentNotNull("iterator", iterator);

        return () -> new IndexedIterator<>(iterator);
    }

    /**
     * Constructs an instance.
     *
     * @param iterator the iterator (must not be {@literal null})
     */
    public IndexedIterator(final Iterator<T> iterator) {
        assertArgumentNotNull("iterator", iterator);

        this.iterator = iterator;

    return (MinimalIterable) of(elements.toArray());
  }

  private @Nullable Iterator<E> iterator;

  private MinimalIterable(Iterator<E> iterator) {
    this.iterator = iterator;
  }

  @Override
  public Iterator<E> iterator() {
    if (iterator == null) {
      // TODO: throw something else? Do we worry that people's code and tests

    assertEquals("b", iterator.previous());
    assertThrows(UnsupportedOperationException.class, () -> iterator.add("c"));
  }

  @SuppressWarnings("DoNotCall")
  public void testSet() {
    ListIterator<String> iterator = create();

    assertTrue(iterator.hasNext());
    assertEquals("a", iterator.next());
    assertEquals("b", iterator.next());
    assertEquals("b", iterator.previous());